Back when Radeon R9 285 was about to launch, our sources confirmed that fully enabled Tonga GPU has a 384-bit memory interface. According to the latest report, AMD never enabled it as it could not hit the perfect price/performance combination.

While AMD Radeon R9 285 was based on Tonga Pro GPU with 1792 Stream Processors and a 256-bit memory interface, we expected to see a fully enabled graphics card based on Tonga XT GPU, with 2048 Stream Processors and a 384-bit memory interface, but that never happened. Instead, AMD decided to recently launched the Radeon R9 380X, which featured a version of the Tonga GPU, rebranded as Antigua and ended up with 2048 Stream Processors as well as a 256-bit memory interface and 4GB of GDDR5 memory.

According to a fresh report from PC Perspective, AMD's Raja Koduri has confirmed that Tonga GPU indeed features a 384-bit memory interface which was intentionally disabled as the company could not hit the right performance/price combination. With a 384-bit memory interface, the R9 380X would need to pack 3GB or 6GB of GDDR5 memory and a more expensive PCB, something that would push the price too close to the Radeon R9 390.

It is still possible that we will see a graphics card based on Tonga GPU with a 384-bit memory interface and either 3GB or 6GB of GDDR5 memory but that is highly unlikely unless AMD decide to do a refresh next year, although we are not sure where it would fit on the market.





Source: PCPer.com.